If you have specific questions about irrigation, or would like additional information please contact Cynthia Turner at 435-5482 or (800) 272-5482.
Since 1999, volatile natural gas prices and in some cases gas availability have led many irrigators to evaluate changing fuel sources. In that same time frame, North Plains Electric Cooperative (NPEC) has seen many producers consider switching from natural gas to electric irrigation and several have already made the switch. We at NPEC have put together this information to help you consider electricity as an option.
Many producers who now use electricity are pleased with the results of the change. Hansford County irrigator Carl Kunselman reports “My cost to irrigate corn last year with electricity was $4.87 per acre-inch. This compares with $5.59 per acre-inch for natural gas and that does not include any labor or maintenance costs such as oil changes and the like.” Pat Patterson, who also farms in Hansford County, said that one positive part of an electric well for him is the convenience. “It is much easier to start and shutdown an electric well. I really like that convenience.” “The fuel is really lower than gas when you run a full month.” But he warns that electricity can be expensive to start and run for only a short period of time. “One of the other hidden benefits of an electric motor is that it can be added to sprinkler insurance, while gas motors usually cannot be insured.”
Ochiltree County irrigator Larry Don Smith echoes the improved convenience and the savings on maintenance and labor. “I like the fact that when I turn on the switch, I’m started and I don’t have to spend so much time getting and keeping the motors running. I save a tremendous amount of time not having to check the wells to see if they are running as often as I did with gas.”
In making a comparison of electricity versus natural gas, the question of what the fuel (energy alternative) will cost is very important, but there are several other considerations to be made. Although fuel use will comprise the largest share of the costs of operation, these other factors will also have a large impact on the operation of the system over time and need to be carefully considered. They include:
Proximity to power lines
Initial purchase price of power unit including pump
Repair and maintenance costs
Labor required to operate and maintain system
Service and parts availability
Future availability of energy source and price stability
Convenience of operation and automation
The first and most important factor to consider in a comparison is proximity to a three phase electric line. At eight dollars per foot to build overhead line, a well located far from power lines is simply not a candidate for electricity. A well fairly close to power lines can be a candidate for conversion because of the NPEC line extension policy. Currently NPEC will provide $3,300 towards construction of a new line to an irrigation well.
In comparing the fuel use, generally it is better to look at a season or a year of operation rather than just on a monthly or hourly basis. The amount spent on electric irrigation can vary significantly from month to month even with a constant rate. The reason for this variability is in the amount of time ran. The NPEC irrigation rate is comprised of a demand charge and an energy charge. Any time a well is started, a demand charge ($4.75 per kilowatt) is charged once a month. This is illustrated in Table 2. If a well only runs one hour this charge is very high on an hourly basis. However, if the well runs 720 hours (24 hours X 30 days), this cost on an hourly basis is very low. Table 1 shows what to expect for demand for a 125 HP electric motor. The other portion of our rate is energy. Although this rate is also constant, it does lower with more use on a monthly basis. The only portion of the irrigation rate that is variable from month to month is the power cost recovery factor or PCRF. This portion of the bill is calculated monthly and accounts for changes in fuel generation costs. The PCRF has averaged ($0.0059181) per kWh over the last three years (2010-2012). Over the summer months (May-August), the PCRF has averaged ($0.0095695). The amount used in calculations in Table 1 and 2 was 0.005 . Table 3 gives a complete breakdown of NPEC’s irrigation rate.
A frequently asked question is “What will happen to the price of electricity as the price of natural gas changes?” The answer is that it will be affected but not on a high level. This is primarily due to the fact that in the summer 25% of the power purchased from Golden Spread Electric Cooperative (GSEC) is generated with coal. In addition, the fact that GSEC does an excellent job of purchasing gas at our plant in Denver City where it has access to three major transmission pipelines. (A complete chart of PCRF in relation to gas prices is available from NPEC by request.)
In Table 1 we have compared theoretical gas and electric 125 horsepower motors and included projected labor and maintenance costs for one year. According to the University of Nebraska Cooperative Extension Service, the labor and maintenance costs for an irrigation motor powered by natural gas are almost 4 times higher that the costs for an electric irrigation motor. The conversion of electric fuel to million cubic feet of gas was calculated using information supplied by Leon New, Texas A&M Professor and Extension Agricultural Engineer. The assumption is that the motor will run 600 hours in June (25 days), 720 hours in July (30 days) and 240 hours in August (10 days). We also assumed a gas price of $5.50/MCF. Monthly minimums are also included in the calculation. At the bottom of the table the potential rebate with the Interruptible Rebate Program is also included. (More information on this program is provided below.)
In Table 2, we have summarized different horsepower wells with different usage patterns and show a natural gas equivalent price based on these two factors. It is important to realize that this table does not include labor and maintenance costs. The PCRF used in these calculations was also ($-0.0059181).
If we can assist you or you have specific questions about irrigation, or anything else, or would like additional information please contact Cynthia Turner at 435-5482 or (800) 272-5482.